Chronic Pain Medications

Studies differ on the prevalence of chronic pain, but a safe estimate would be between 15-25% of the general population has chronic pain.1, 2

Most people with chronic pain do not seek healthcare for it on a regular basis.3 Presumably, they are neither distressed nor impaired enough to seek care. However, some people do suffer from chronic pain and consequently seek recommendations from healthcare providers.

Patients often tend to look to their healthcare providers to prescribe a medication to help reduce pain. There are many common medications for chronic pain:

Anti-inflammatory medications & acetaminophen

Muscle relaxant medications

Antidepressant medications (used for pain)

Anticonvulsant medications (used for pain)

Opioid, or narcotic, medications

It is important to know something of their use and relative effectiveness.

Anti-inflammatory medications & acetaminophen

Anti-inflammatory medications and acetaminophen are commonly used for pain. On average, these medications have been shown to be mildly to moderately effective in reducing chronic pain.4 The quality of this research is good.5

Muscle relaxant medications

In their review of the research, Chou and Huffman5 found that muscle relaxants, on average, were moderately helpful in reducing acute back pain. Studies testing the effectiveness of muscle relaxants for chronic pain are lacking.

Antidepressant medications

As the name suggests, antidepressant medications were originally developed for use with depression. However, they have long been known to reduce chronic pain and are commonly used for such purposes.

In meta-analyses, antidepressant medications are moderately helpful in reducing chronic pain, but do not tend to improve daily functioning.6, 7 Tricyclic antidepressants, in particular, have the best quality of research evidence supporting their effectiveness.

Anticonvulsant medications

Anticonvulsant medications are medications that were originally developed for the management of seizures. However, they have also been shown to be helpful in managing nerve pain.

While noting the effectiveness of anticonvulsant medications for nerve pain, Chou and Huffman5 report that they found only one study of the effectiveness of anticonvulsant medications for chronic back pain. The study showed that topiramate is modestly better than placebo.

Opioid, or narcotic, medications

Opioid, or narcotic, pain medications are commonly used for chronic pain. Despite their common use, there is little research on the long-term effectiveness of opioids for chronic pain.10 In their review of this research, Kroenke, Krebs, and Bair11 found that, when used on a short-term basis, opioid medications are modestly better at reducing pain than a placebo. However, they also found that opioids were no better than non-narcotic pain medications at reducing pain. Moreover, they found that opioid medications were slightly less effective than non-narcotic pain medications on functional outcomes.

In their meta-analysis of the research, Martell, et al.,12 found that opioid medications are no better than placebo when it comes to reducing pain.

Ballantyne and Shin13 reviewed evidence showing that opioids lose their effectiveness over time because of tolerance. Tolerance is the phenomenon that occurs when the body gets adjusted to the use of a medication over time and, as such, the medication loses its effectiveness. Tolerance occurs with opioid medications. As a result, patients commonly need periodic increases in their dose of opioids in order to get the same level of pain relief.

Tolerance is a significant problem. Assuming a normal lifespan, most patients eventually get tolerant to even the highest doses of opioids long before they get elderly. As such, they essentially buy pain relief today at the cost of having the medications become no longer effective for them in the future, should they have an altogether different injury or require a surgery.

Addiction, of course, is also a significant problem. The pain management field defines addiction as a loss of control over the use of opioid medications or continued use of the medications despite harm.14 In their meta-analysis cited above, Martell, et al.,12 found that upwards of 20% of patients on opioid pain medications demonstrate problematic behaviors that are suggestive of addiction.

5. Chou, R., & Huffman, L. H. (2007). Medications for acute and chronic low back pain: A review of the evidence for an American Pain Society/American College of Physicians clinical practice guideline.Annals of Internal Medicine, 147, 505-514.

Murray J. McAllister, PsyD, is the editor and founder of the Institute for Chronic Pain (ICP). The ICP is an educational and public policy think tank. Its mission is to lead the field in making pain management more empirically supported. Additionally, the ICP provides Academic quality information on chronic pain that is approachable to patients and their families. Dr. McAllister is also the clinical director of pain services for Courage Kenny Rehabilitation Institute (CKRI), part of Allina Health, in Minneapolis, MN. Among other services, CKRI provides chronic pain rehabilitation services on a residential and outpatient basis.